MOSCOW: Russia, Ukraine, Belarus and Kazakhstan are working on plans for a joint economic zone, the presidents of the four former Soviet republics said in a statement on Sunday.

The documents laying out the formation of the new grouping, which will start with the creation of a free trade zone, are expected to be ready in September.

A joint commission based in the Ukraine capital of Kiev will be responsible for setting customs and tariffs that will be binding for all four members, the news agency Interfax reported.

The new organisation takes things further than the current customs union between Russia and some of the other former Soviet republics linked in the Commonwealth of Independent States (CIS), a Kremlin spokesman said.

The formation of a free trade zone was discussed at an informal CIS summit in January.

Trade between the former Soviet republics is lower today that it was during the time of the Soviet centrally planned economy.

Russian Trade Minister German Gref said wide-ranging changes would be necessary in all four states before the formation of a common economic zone. He said the September deadline was “extremely tight”.—dpa